This invention relates to blood separation devices. More particularly, the invention concerns a device for the removal of the serum which is separated from the blood cake through centrifugation of a test tube, closed at least on one side by a plug, the device comprising a top which is essentially rotationally symmetrical and which is furnished with a first collar encircling the plug and a cannula which penetrates the plug, and comprising a serum container for receiving the part of the serum which settles during centrifugation in the test tube.
A test tube for receiving a blood sample which is to be separated through centrifugation is known from DE-OS 27 11 336. This test tube receives a separating body, the specific gravity of which is between those of the two components of the blood to be separated. The separating body moves during centrifugation between the two components and separates the components after completion of the centrifugation by blocking the diameter of the separation tube. This test-tube construction is easy to handle. It may be felt to be a disadvantage that the sample container in this system is not closed.
In addition, a device is known which removes the serum of a blood sample to be separated through centrifugation into blood cake and serum with the prior art features of claim 1. For transferring the serum into a special serum container the rubber plug is penetrated by a cannula which is set on a top which is to be pushed onto the rubber plug. A sucking tube which is attached to a serum container is introduced into the cannula which penetrates the rubber plug. Serum is now pumped by means of a special vacuum pump from the test tube into the serum container.
This system has the disadvantage that the serum has to be pumped by a special pump from the test tube into the serum container after centrifugation.